#include <fstream>
#include <vector>

using namespace std;

ifstream in("dfs.in");
ofstream out("dfs.out");


int n,m,nc[100001],comp;
vector<int>a[100001];
bool viz[100001];

void dfs(int nod)
{
    viz[nod]=true;
    for(auto y:a[nod])
    if(!viz[y])
    {
        dfs(y);
    }
}

int main()
{in>>n>>m;
for(int i=1;i<=m;i++)
{
    int x,y;
    in>>x>>y;
    a[x].push_back(y);
    a[y].push_back(x);
}
 for(int i=1;i<=n;i++)
 {
     if(!viz[i])
     {
        comp++;
        dfs(i);
     }
 }
    out<<comp;
    return 0;
}